JP2015024123A - Film for excrement bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film for an excrement bag having excellent biodegradability and hydrolysis resistance.SOLUTION: A film for an excrement bag has a layer comprising a 3-hydroxyalkanoate copolymer having a 3-hydroxybutyrate unit and a 3-hydroxyhexanoate unit, and a biodegradable resin other than the 3-hydroxyalkanoate copolymer. The biodegradable resin other than the 3-hydroxyalkanoate copolymer is preferably polybutylene adipate terephthalate.

Description

  The present invention relates to a film excellent in biodegradability and hydrolysis resistance, which is used in a waste bag containing waste excreted from an artificial anus.

  When the digestive tract or urinary tract is damaged due to illness or accident, the intestinal tract or urinary tract is led to the body surface in the abdomen, etc., forming an opening (stoma), and the excrement from the body is temporarily excreted. The method of accommodating in the bag is taken.

  As a material constituting the excrement bag, multilayer films such as polyvinylidene chloride, polyethylene, and ethylene-vinyl acetate copolymer are known.

  However, the conventional excrement bag has a problem in terms of processing the excrement to be accommodated. That is, the excrement bag needs to be discarded when the excrement becomes a certain amount, but when it is discarded, the stored excrement must be washed out. Moreover, even if it is washed, it is not hygienic to dispose of the excrement bag as waste, and the burden on the environment is unavoidable.

  In response to such problems, the excrement bag can retain mechanical strength for a certain period of time while containing excrement, and after use it can flow to a flush toilet while containing excrement. Known (Patent Document 1). However, it has been very difficult to balance the mechanical strength and water resistance required during use with the water solubility required during washing.

  Moreover, in order to reduce the load to an environment, the excrement bag which consists of a biodegradable resin film is also known (patent document 2). The biodegradable resin film described in Patent Document 2 is a mixture of a polylactic acid resin and a polyethylene succinate resin, but the polylactic acid resin is very hard and is required to be flexible as a waste bag. May be inferior. Moreover, since hydrolysis resistance is not enough, it was unbearable for a long-term use.

JP 2007-37881 A JP 2005-313998 A

  The present invention has been variously studied to solve the above problems. As a result, a 3-hydroxyalkanoate copolymer having 3-hydroxybutyrate units and 3-hydroxyhexanoate units, and the 3-hydroxyalkanoate copolymer It has been found that when a waste bag is composed of a biodegradable resin film having a layer containing a biodegradable resin other than coalescence, the biodegradability and hydrolysis resistance are excellent, and the present invention has been completed.

The present invention has been made under such knowledge, and the gist thereof is as follows.
(1) A layer comprising a 3-hydroxyalkanoate copolymer having 3-hydroxybutyrate units and 3-hydroxyhexanoate units, and a biodegradable resin other than the 3-hydroxyalkanoate copolymer A film for excrement bags, comprising:
(2) The excrement bag film according to (1), wherein the biodegradable resin other than the 3-hydroxyalkanoate copolymer is polybutylene adipate terephthalate.

  Since the excrement bag film of the present invention has hydrolysis resistance, it can be used over a long period of time. Further, when the excrement bag is discarded, it is biodegraded, which is very useful from the viewpoint of protecting the natural environment and the problem of waste disposal.

  Hereinafter, the present invention will be described in detail. The film for excrement bags of the present invention includes a 3-hydroxyalkanoate copolymer having 3-hydroxybutyrate units and 3-hydroxyhexanoate units and biodegradability other than the 3-hydroxyalkanoate copolymer. And a layer containing a resin.

The 3-hydroxyalkanoate copolymer used in the present invention has 3-hydroxybutyrate units and 3-hydroxyhexanoate units.
In the 3-hydroxyalkanoate copolymer, the content of 3-hydroxybutyrate units is preferably 95 to 80 mol%, and the content of 3-hydroxyhexanoate units is preferably 5 to 20 mol%. When the content of the 3-hydroxybutyrate unit exceeds 95 mol%, the crystallinity increases, and the film tends to become hard or brittle. On the contrary, when the content of 3-hydroxybutyrate unit is less than 80 mol%, the crystallinity is lowered and the melting temperature is lowered, so that film forming tends to be difficult.

  In the 3-hydroxyalkanoate copolymer, in addition to 3-hydroxybutyrate unit and 3-hydroxyhexanoate unit, 3-hydroxyvalerate, 3-hydroxyoctanoate, 3-hydroxy as necessary. Monomer units such as decanoate may be copolymerized.

In the 3-hydroxyalkanoate copolymer, the weight average molecular weight is preferably 300,000 to 3,000,000, and more preferably 500,000 to 2,000,000. If the weight average molecular weight of the hydroxyalkanoate copolymer is 300,000 or more, sufficient mechanical properties can be secured, and if it is 3 million or less, processability is improved.
In addition, the weight average molecular weight here is a value obtained by measuring by gel permeation chromatography using polystyrene as a standard substance.

The 3-hydroxyalkanoate copolymer can be produced by a fermentation synthesis method using a microorganism. The microorganism used in the fermentation synthesis method is not particularly limited as long as it is a microorganism that accumulates a 3-hydroxyalkanoate copolymer in a cell. lipolytica, A.I. eutrophus, A.M. Examples include Alcaligenes, such as latus, Pseudomonas, Bacillus, Azotobacter, Nocardia, Aeromonas and the like. Among them, in terms of efficiently producing a 3-hydroxyalkanoate copolymer, in particular, strains such as Aeromonas caviae (Aeromonas genus), and further, Alcaligenes eutrophus AC32 (FERM BP-6038) into which genes of PHA synthase group have been introduced. (J. Bacteriol., 179, p4821-2830 (1997)) and the like, and microbial cells obtained by culturing these microorganisms under appropriate conditions and accumulating 3-hydroxyalkanoate copolymer in the cells Is used.

  As the biodegradable resin other than the 3-hydroxyalkanoate copolymer used in the present invention, aliphatic polyesters and derivatives thereof can be used. For example, polybutylene adipate terephthalate, polybutylene succinate, polybutylene succinate. Nate adipate, polycaprolactan, polylactic acid and the like. Among these, polybutylene adipate terephthalate, which is excellent in flexibility and piercing strength, is preferable.

  The blending ratio of the 3-hydroxyalkanoate copolymer and the biodegradable resin other than the 3-hydroxyalkanoate copolymer is 50 to 95% by weight of the 3-hydroxyalkanoate copolymer, 3-hydroxyalkanoate copolymer The biodegradable resin other than coalescence is 5 to 50% by weight. If the 3-hydroxyalkanoate copolymer is less than 50% by weight, the hydrolysis resistance is poor, and if it exceeds 95% by weight, film formation becomes difficult.

The excrement bag film of the present invention comprises at least a layer comprising the 3-hydroxyalkanoate copolymer and a biodegradable resin other than the 3-hydroxyalkanoate copolymer.
That is, it may be a single-layer film consisting only of a layer comprising a 3-hydroxyalkanoate copolymer and a biodegradable resin other than the 3-hydroxyalkanoate copolymer, or a 3-hydroxyalkanoate copolymer. It may be a multilayer film formed by laminating a layer comprising a polymer and a biodegradable resin other than the 3-hydroxyalkanoate copolymer and a layer having biodegradability or other functionality. .

  In the case of a multilayer film, the layer comprising a 3-hydroxyalkanoate copolymer and a biodegradable resin other than the 3-hydroxyalkanoate copolymer is the innermost layer (when the waste bag is formed). The inner layer is preferable.

In the case of a multilayer film, a layer other than a layer comprising a 3-hydroxyalkanoate copolymer and a biodegradable resin other than the 3-hydroxyalkanoate copolymer is used according to its purpose. Resin can be selected.
If biodegradability is required as the entire excrement bag film, a laminated structure with a layer made of a biodegradable resin is used. Examples of the biodegradable resin include polybutylene adipate terephthalate, polybutylene succinate, polybutylene succinate adipate, polycaprolactan, and polylactic acid.
For the purpose of improving odor barrier properties, it is preferable to provide a layer made of polyvinylidene chloride resin and saponified ethylene-vinyl acetate copolymer (EVOH).
Further, a layer made of vinyl chloride resin or olefin resin may be provided. Specifically, the olefin resin was selected from a homopolymer such as polyethylene, polypropylene, polybutene-1, ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, and the like. A copolymer of α-olefins or a copolymer of an α-olefin and another copolymer component may be mentioned. Examples of copolymer components other than α-olefin include diolefin, vinyl chloride, vinylidene chloride, vinyl acetate, styrene, acrylonitrile, vinyl ether and other vinyl compounds, maleic acid, acrylic acid, methacrylic acid, fumaric acid, and itaconic acid. Saturated carboxylic acid etc. are mentioned. Α-olefin / α, β
An ionomer resin that is a reaction product of an unsaturated carboxylic acid and an ionic metal compound can also be used.

In the case of the multi-layer structure, an adhesive layer may be provided between the layers in order to ensure the adhesion of the layers.
The resin used for the adhesive layer is not particularly limited, but a resin obtained by graft-modifying an olefin resin with an unsaturated carboxylic acid or an anhydride thereof (such as maleic anhydride) is preferably used.

Moreover, it is preferable to mix | blend a deodorizing agent with the layer which comprises the film for excrement bags of this invention. By adding such a deodorizing agent, the odor barrier property of the excrement bag is improved.
The deodorizing agent to be blended is a substance having a deodorizing effect on various malodorous components, for example, ammonia, amine, hydrogen sulfide, mercaptan, sulfide, etc., specifically, organic acids, iron compounds, zinc compounds, aluminum compounds, A copper compound, a silicon compound, a zirconium compound, a zeolite, Iooh stone, etc. are mentioned. These deodorizers can be used alone or in combination of two or more.

  In addition to the above deodorizer, various additives can be blended in the respective layers constituting the excrement bag film of the present invention as required. Examples of such additives include antioxidants, plasticizers, heat stabilizers, lubricants, colorants, fillers, and the like.

  The thickness of the excrement bag film is not particularly limited, but the total thickness is preferably 10 to 200 μm, more preferably 50 to 150 μm. When the total thickness exceeds 200 μm, there is a problem that the rigidity of the film is increased and the flexibility is lowered, and the weight of the bag is increased. In addition, if the total thickness is less than 10 μm, there is a problem that the mechanical strength is low and it is easily broken, or the sound absorption is low and sound leakage at the time of excretion becomes easy.

  The method for molding the excrement bag film of the present invention is not particularly limited, but in the case of a single layer film, extrusion molding, inflation molding, calendar molding, in the case of a multilayer film, coextrusion molding, dry Laminate molding or the like can be employed.

  By processing the above excrement bag film into a bag shape, it can be used as an excrement bag. Examples of the method for processing into a bag include a high-frequency welder and a heat seal.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited by these Examples.

<Examples 1-6, Comparative Examples 1-2>
T-die extrusion molding was carried out with the formulation shown in Table 1 to produce a film having a thickness of 100 μm.
The unit of the numerical values in the table is “% by weight”.

In the table;
3-hydroxyalkanoate copolymer 1
Aonilex manufactured by Kaneka Corporation (3-hydroxybutyrate 94 mol%, 3-hydroxyhexanoate 6 mol%)
-3-hydroxyalkanoate copolymer 2
Aonilex manufactured by Kaneka Corporation (3-hydroxybutyrate 89 mol%, 3-hydroxyhexanoate 11 mol%)
・ PBAT (Polybutylene adipate terephthalate)
Ecoflex PBS (polybutylene succinate) manufactured by BASF Japan
Bionore # 1001 manufactured by Showa Polymer Co., Ltd.
・ PBSA (Polybutylene succinate adipate)
Bionore # 3001 by Showa Polymer Co., Ltd.
The unit of the numerical values in the table is “% by weight”.

  The following evaluation was performed about the obtained film.

<Molding processability>
During film forming, it was visually confirmed whether the resin was stably coming out of the die.
○ ・ ・ ・ No problem × ・ ・ ・ Stable resin is not supplied to the die

<Hydrolysis resistance>
A test piece of 5 cm × 5 cm was cut out from the obtained film, immersed in water adjusted to 60 ° C. × 50% RH, the weight change after 2 weeks was confirmed, and evaluated as follows. Rate is less than 20% × ・ ・ ・ Weight change rate is 20% or more

Examples 1 to 6 are suitable as a film for excrement bags because of excellent molding processability and hydrolysis resistance.

Claims (2)

  A layer comprising a 3-hydroxyalkanoate copolymer having 3-hydroxybutyrate units and 3-hydroxyhexanoate units, and a biodegradable resin other than the 3-hydroxyalkanoate copolymer; A film for excrement bags.   The film for excrement bags according to claim 1, wherein the biodegradable resin other than the 3-hydroxyalkanoate copolymer is polybutylene adipate terephthalate.